The present invention relates to a method of making a thermal transfer type multicolor printing by the use of transfer ribbons which carries a plurality of heat-dissolving inks.
With the wide use of color cathode ray tubes (CRT) in the display of personal computors and CAD systems, there has been a strong need for a printer which provides multicolor hardcopies of pictures on color CRT. In order to meet such need, there has been developed, for instance, the ink jet type multicolor printing method, but this method is complicated in operation processes and is liable to produce mechanical troubles in ink clogging in ink nozzles.
Among the other type of printing methods, there is the thermal transfer printing method, in which thermal patterns are applied to a heat-sensitive paper by means of a thermal head to thereby carry out a monocolor printing on that paper, or to an ink transfer ribbon to transfer a heat-dissolving ink, which is applied over that transfer ribbon, onto a printing paper whereby monocolor printing is carried out. For example, U.S. Pat. No. 4,334,231 discloses a thermal printer for printing the content of a display screen on thermally sensitive paper. The disclosure of that patent is incorporated herein by reference. Such a type of method is less complicated in operation and hence mechanical troubles are less liable to occur, but it is restricted to monocolor printings. Any multicolor printing method of the thermal transfer type has not yet been put into practical use.